/Engine/Plugins/Animation/ControlRig/Source/ControlRig/Public/Rigs/RigHierarchyController.h
Returns the modified event, which can be used to subscribe to topological changes happening within the hierarchy.
The event used for subscription.
[FRigHierarchyModifiedEvent](API\Plugins\ControlRig\Rigs\FRigHierarchyModifiedEvent) & OnModified()